Search results for "Rate"

Geological Setting and Paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola

2014

AbstractThe Bench 19 Bonebed at Bentiaba, Angola, is a unique concentration of marine vertebrates preserving six species of mosasaurs in sediments best correlated by magnetostratigraphy to chron C32n.1n between 71.4 and 71.64 Ma. The bonebed formed at a paleolatitude near 24°S, with an Atlantic width at that latitude approximating 2700 km, roughly half that of the current width. The locality lies on an uncharacteristically narrow continental shelf near transform faults that controlled the coastal outline of Africa in the formation of the South Atlantic Ocean. Biostratigraphic change through the Bentiaba section indicates that the accumulation occurred in an ecological time dimension within …

Venerid bivalve Venus verrucosa as a high-resolution archive of seawater temperature in the Mediterranean Sea

2021

Abstract High-resolution stable isotope data (δ18O, δ13C) were used to study growth strategies of the bivalve Venus verrucosa collected from three sites of the eastern coast of the Adriatic Sea. The principal objectives of this study were to identify the main growing season and to evaluate the potential applicability of δ18Oshell values to reconstruct the seasonal temperature variability. Calcium carbonate for oxygen and carbon isotope analyses was obtained by drilling the outer shell layer. Temporal and spatial variations in temperature and salinity values at the study sites were simulated using the 3D numerical ocean model ROMS. Annual periodicity of growth patterns was confirmed by δ18Os…

Soil physicochemical and microbial drivers of temperature sensitivity of soil organic matter decomposition under boreal forests

2020

Abstract Soil organic matter (SOM) in boreal forests is an important carbon sink. The aim of this study was to assess and to detect factors controlling the temperature sensitivity of SOM decomposition. Soils were collected from Scots pine, Norway spruce, silver birch, and mixed forests (O horizon) in northern Finland, and their basal respiration rates at five different temperatures (from 4 to 28 °C) were measured. The Q10 values, showing the respiration rate changes with a 10 °C increase, were calculated using a Gaussian function and were based on temperature-dependent changes. Several soil physicochemical parameters were measured, and the functional diversity of the soil microbial communit…

Letter to the editor regarding the article “Taking advantage of seagrass recovery potential to develop novel and effective meadow rehabilitation meth…

2020

Alagna et al. (2019) suggest new transplantation methods for Posidonia oceanica (Linnaeus) Delile, inspired by its natural recovery process after disturbance due to dredging operations for gas-pipelines. They observe that P. oceanica vegetative fragments naturally settled only on loose calcareous stones deployed to fill the trenches of the gas-pipeline. No recovery was noted on dead matte, sand and large calcarenitic boulders. Following a new pilot restoration project currently ongoing in the same area, we demonstrate that natural recovery also occurs on dead matte. After examining other alternative transplantation methods for P. oceanica, the Authors suggest using their "habitat enhancemen…

Patterns of drought tolerance in major European temperate forest trees: climatic drivers and levels of variability

2013

The future performance of native tree species under climate change conditions is frequently discussed, since increasingly severe and more frequent drought events are expected to become a major risk for forest ecosystems. To improve our understanding of the drought tolerance of the three common European temperate forest tree species Norway spruce, silver fir and common beech, we tested the influence of climate and tree-specific traits on the inter and intrasite variability in drought responses of these species. Basal area increment data from a large tree-ring network in Southern Germany and Alpine Austria along a climatic cline from warm-dry to cool-wet conditions were used to calculate indi…

Implementation of IUCN criteria for the definition of the Red List of Ecosystems in Italy

2020

The present work is aimed at presenting the data, methods and criteria that are being used for the assessment of ecosystem collapse risk in Italy.

2021

Invertebrate communities of the High Arctic ponds in Hornsund

2016

How environmental conditions influence current distributions of organisms at the local scale in sensitive high Arctic freshwaters is essential to understand in order to better comprehend the cascading consequences of the ongoing climate change. This knowledge is also important background data for paleolimnological assessments of long-term limnoecological changes and in describing the range of environmental variability. We sampled five limnologically different freshwater sites from the Fuglebergsletta marine terrace in Hornsund, southern Svalbard, for aquatic invertebrates. The invertebrate communities were tested against non-climatic environmental drivers (limnological and catchment variabl…

Decreasing in patch-size of Cystoseira forests reduces the diversity of their associated molluscan assemblage in Mediterranean rocky reefs

2021

Abstract Canopy-forming seaweeds of the genus Cystoseira (Fucales, Phaeophyceae) form diverse and productive habitats along temperate rocky coasts of the Mediterranean Sea. During the last decade, Cystoseira forests have retracted their range considerably due to many interacting environmental, biological and anthropogenic pressures. We investigated how reducing in patch-size of C. montagnei affects their associated molluscan communities at the shallow northwest rocky shores of Palermo (Sicily, Italy). Molluscs were sampled from the fronds of individual thalli, clumps of 3 and 5 thalli of C. montagnei over an annual vegetative cycle (May–September) in two sites within the Marine Protected Ar…

Environmental drivers interactively affect individual tree growth across temperate European forests

2019

Forecasting the growth of tree species to future environmental changes requires a better understanding of its determinants. Tree growth is known to respond to global-change drivers such as climate change or atmospheric deposition, as well as to local land-use drivers such as forest management. Yet, large geographical scale studies examining interactive growth responses to multiple global-change drivers are relatively scarce and rarely consider management effects. Here, we assessed the interactive effects of three global-change drivers (temperature, precipitation and nitrogen deposition) on individual tree growth of three study species (Quercus robur/petraea, Fagus sylvatica and Fraxinus exc…